Back ground: -Every pregnancy is a risk which may end up with complication or death.rnInstitution delivery is a good means to undertake this risk in providing the delivery service byrnskilled personnel and which will contribute to reduce maternal morbidity and mortalityrnespecially for developing countries like Ethiopia.rnObjective:-This study was designed and conducted with the aim of assessing factors influencingrnmagnitude and utilization of institutional delivery in Nifas Silk Lafto Sub-city in Addis Ababa,rn2014.rnMethods:-A community based cross sectional study using quantitative methods was conductedrnin Nifas Silk Lafto Sub city, Addis Ababa. A study population was all six ketenaâ€™s in Woredarntwo of the sub-city. The total sample size for the study was estimated by single proportionrnpopulation formula. Data was collected from 794 women of reproductive age using structuredrnquestionnaire, EPI-info version 3.5.1 was used to enter the data and SPPS version 20.0 wasrnemployed for analysis. Logistic regression and odds ratio was calculated to ascertain associationrnbetween dependent and independent variable. The result was present in tables and text.rnResultrnA total of 768 women of reproductive age participated in this study. Women who have higherrnlevel of education were about 3.6 times more likely to deliver at health institution compared tornwomen with low level of education [AOR: 3.6, 95% CI: (1.1 , 11.8)].The study also showed thatrn92.9% of mothers gave birth in health institution.rnConclusion: - This study highlighted institutional delivery is most favorable so that promotingrninstitutional delivery and women education is crucial among women of reproductive age group